Heat exchanger



y 9, 1933. J. A. POTTER 1,907,867

HEAT EXCHANGER Filed Dec. 2 1931 2 Sheets-Sheet 1 35-42 I* orlQcw (o,goooooooooo /{oooooo I 000 9. 44 00000000 0o 45 az-- o 000 wipoooooooooo a E? 000009 000 [MENTOR WITNESS W @l JOHN H. POTTER 6 FIG.3- .4 rum/v5 Y May 9, 1933.

J. A. POTTER HEAT EXCHANGER Filed Dec. 1931 2 Sheets-Sheet 2 INVENTORJOHN H. POTTER I (1,. I5, M

A TTOR/Vli J Patented May 9, 1933 UNITED STAT-Bis.

PATENT OFFICE :omw a. roma; or mooansrnnnsnvma, assrcuoa r wns'rxiwnousnmum a mmac'ruamc commmr, a coaroaa'rxon or rmmmvma HEAT EXCHANGE-BApplication filed December 22, 1981. Serial No. 588,617.

My invention relates to heat exchange ap-- paratus, and it has for anobject to provide, an improved means for supporting portions of thetubing thereof.

This invent1on is particularly applicable ing. It will be apparent thatthe conven tional solid tube sheet for supporting the tubingintermediately of the length thereof is out of the question, as the tubewith fins attached would not pass through the holes in the tube sheetwhen being replaced.

It has been proposed to provide a solid tube sheet with holes largeenough for the fins to pass through when the tube is being replaced.With this construction, the fins ofthe tubing rest on the bottom of eachhole in the tube sheet to support an intermediate portion of, the tube.It will be apparent that this is an undesirable arrangewould have to beincreased over a desirable amount; otherwise the thickness of metalbetween holes in the tube sheet would be very thin. Furthermore, it is apoor arrangement to carry the weight of the tubes through the fins whichare usually 'of thin material. a

It is, therefore, a further object of my invention to provide animproved supportin means for finned tubing, that will provi e for therenewing of tubes, and which will be free from the disadvantagesoutlined 2 above.

essary may be provided. Furthermore, this arrangement is also verydesirable for sup porting the free or floating ends of a hairpin t etube, whether it be a plain or a finn tube.

A further object of my invention is to provide a supporting structurefor heat exchange tubes which structure embodies a plurality of elementscarriedby the tubes and which engage one another in stacked relationwhen the tubes are assembled in a heat exchanger, a portion of whichcarries the stacked elements. 5 These and other objects are eflected bym invention, as will be a parent from the f0 lowing description anclaims taken in connection with the accompanying drawings, forming apart of this application, in whic Fig. 1 is a plan view of a heatexchanger embodying my improved supporting structure;

Fig. 2 is a side view of the heat exchanger shown in Fig. 1 with partsbroken away;

Fig. 3 is an end view of the heat exchanger shown in Fig. 2 and ispartly in end elevation with a cover removed and a partlfi in ment asthe pitch or distance between tubes ctlon taken along the hue II I of-Fig. 2.

F1 4 IV-%V of Fig. 2;

Fig. 5 is a side elevation, with parts broirege away, of a heatexchangerusinghairpin Fig 6 is a fragmentary plan view of .Fig. 5;

Fig. 7 is a sectional view of a detail and is taken on line VIIVII ofFig. 5;

Fig. 8 is a plan view of a finned type hairtg 1 m f 1g. 1s a artia viewin tive o myimproved tinned tube; an

Fig. 10 is a view similar to Fig. 9 illustrating a plain tube.

Referring now to Figs. 1 to 4, I prefer to show a heat exchanger that isused for air cooling, and which includes a plurality of tube bundleunits 10, each of which includes aseries of finned tubes 11 secured atone end in tube plate sections 12, 12a, 12b and 120. The opposite endsof all of the tubes 11 are secured in a unitary tube plate 13.

is a sectional view taken aloiig line While I have shown a finned tubein this embodiment as preferable, it will be understood that the plaintube 11a shown in Fig. 10 may be used. The tube bundle construction issimilar to that disclosed in my copending application, Serial No.507,017 filed January 6, 1931 and assigned to the Westinghouse Electricand Manufacturing Company.

The tube plate sections 12 to 120 may be secured together in the mannerdisclosed in the application referred to, but I prefer to show themaligned by and secured to a perforated tube sheet 14; whichconstruction-is disclosed and claimed in the copending application ofErnest F. Miller, Serial No. 583,521, filed Dec. 28, 1931 and assignedto the Westinghouse Electric and Manufacturing Company. Thisconstruction is best understood by referring to Figs. 2 and 4. The tubeplate sections 12 and 120 are secured to the tube sheet 14, preferablyby bolts 15. The tube sheet 14 has openings 16, which are aligned withthe tubes 11, and provided communication between the tubes 11 andchambers 17 and 18. The chambers 17 and 18 are formed by the tube sheet14, walls 19 and 21, and a cover 22 which is secured to the tube sheet14 by bolts 23. The tube sheet 14 is secured by bolts 24 to transverseangle irons 25 forming a part of a shell structure 26.

.The unitary tube sheet 13 is secured to the shell structure 26,preferably by bolts 27, and has secured thereto a box structure 28 whichincludes the inlet 29 and an outlet 31 for the cooling medium. The boxstructure includes partitions 32 to form chambers 33, the number ofwhich depends on the num ber of passes the cooling medium makes intraversing the tube nest. The heat exchanger shown is of the four-passtype, although it will be understood that my invention is applicable toa heat exchanger of any number of passes. A cover 34 is secured to thetube plate 13 by means of bolts 35.

The shell structure 26 includes side walls 36 and 37 which with tubesheets 13 and 14 form an enclosure for the tube bundle units 10. The topand bottom of the shell structure are open forming an inlet 38 and anoutlet 39 for media to be cooled.

A bar 41 extends transversely of the tubes 11 and is secured to theshell structure 26, preferably by bolts 41a. This bar 41 is thefoundation of the support of the intermedigaged forming a stack as bestshown in Fig. 3. The lower row of blocks 42 rest on the bar 41 whichprovides a foundation for the stacked blocks. A tortuous path for mediato be cooled is provided by staggering the vertical rows of blocks,which is a preferred arrangement. Deflecting bafiles 46. may be spacedin the shell 26 to direct over the tubes 11 the media passing throughthe shell. These bafiles 46 extend from the tube sheet 13 to the tubeplate sections 12 to 120 and are secured thereto.

In operation, a cooling medium enters the inlet 29, passes through thetubes 11, and the chambers 17, 18, and 33, and continues through theoutlet 31. Media to be cooled enters the shell structure 26 throughinlet 38, traverses the cooled tubes 11, and passes through the outlet39. In apparatus of this class, provision must be made for the removaland renewal of tubes which have become defective in operation. Themethod of removing a tube from thetube bundle is similar to thatdescribed in my copending application referred to above and is asfollows:

The bolts 23 and cover 22 are removed from the tube sheet 14 and walls19, providing access to the bolts 15 which are also removed. Bolts 35and cover 34 are next removed. The bolts 41a are removed and thefoundation bar 41 dropped. This is desirable, as otherwise the tube fins45 may be damaged as the intermediate portion of the tubes will sag assoon as the supporting blocks 42 leave the bar 41 when the bundle isbeing removed. The bolts 27 are next removed and the tube bundle units10, including tube sheet 13 and the tube sheet sections 12 to 120, arewithdrawn from the end of the shell 26.

Assuming the. tube 48 to be defective, it is cut internally at both endsadjacent the tube sheet 13 and section 120. The tube sections 120 and126 are then pried apart, the tubes 11 of each section together with thebafiles 46 deflecting to permit this movement. This operation providesaccess to the tube 48 and it is withdrawn through the space providedbetween the adjacent sections 12b and 120. In withdrawing the tube 48,the block 42 carried thereby, leaves the stack and as the surfaces ofthe block are outwardly of the outer edge of the fin 45, the finsreadily pass through the opening in the stack caused by the removal ofthe block 42. A new tube is then inserted, the tube ends remaining inthe sheets having been removed, and the tube bundle reassembled in theshell, the steps in this operation being the reverse of the dismantlingoperation.

Referring now to Figs. 5 to 8, I have shown a heat exchanger 50utilizing hairpin tubes which may be plain as shown in Figs. 5, 6 7 orfinned as shown at 52 in Fig. 8. The heat exchanger includes 0 a shell53 having side walls 54 and 55 and an end wa1l56. One end of the shell53 is closed by a tube plate 57 in which the tubes 51 are secured. Aheader 58 is attached to the tube plate 57 and communicates with thetubes 51 to convey a heat exchan e medium to and away therefrom. Theeader further includes inlet and outlet connections 59 and 61,respectively, for the heat exchange medium and a cover 62 for the largehead opening 63.

Each of the tubes 51 has a plurality of blocks 64 secured theretoalthough but one block would be necessary on a relatively short tube.Preferably, the blocks 64 embrace both legs 65 of the tubes 51.

Foundation bars 66 are arranged below the tubes 51 and are secured tothe shell 53, preferably by bolts 67. When the tubes are arranged withinthe shell 53 in a bundle, the blocks 64 are aligned one with the otherin stacks best shown in Figs. 5 and 7. The blocks 64 engage one anotherproviding a support for the'tubes, the bottom rows of the blocks 64 arearranged outwardly of the edge of the fin as in the prior embodiblocksresting on the foundation bars 66.

When it is necessary to renew a tube, the tubes 51 are withdrawn fromthe shell 53 .and the cover 62 removed from the header 58 to gain accessto the ends of the tubes 51. Both legs of the tube are internally cutadjacent the tube plate 57, and the defective tube withdrawn from thebundle. A new tube is then inserted and rolled into or otherwise securedto the tube plate 57 and the heat exchanger is then assembled. Thisprocedure is the same for a finned tube as for a plain tube. As thecontact surfaces 68 on ment, the opening, left in the stacked blocks dueto the removal of the block 64 on the tube being removed, will be largeenough to permit the fins to pass through.

From the foregoing description, it will be seen that I have devised asupporting means for the intermediate portion or for the floating end ofa heat exchange tube that will fulfill its purpose and which will permitthe renewal of tubes regardless of type. While I have shown my inventionas applied to air coolers, it will be apparent to those skilled in theart that this supporting structure could be applied to heat exchangersfor other services.

While I have shown by invention in two forms, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications, without departing from thespirit thereof, and I desire, therefore, that only such limitationsshall be placed thereupon as are imposed by the prior art or as alrespecifically set forth in the appended aims.

What I claim is:

1. In a heat exchanger, the combination of a shell structure, aplurality of groups of finned tubes disposed therein; each of saidgroups including a series of tubes and a tube plate section in which oneend of the tubes is secured; a unitary tube sheet at the opposite end ofthe tubes in which all of the tubes are secured, means for supportingsaid tube plate sections substantially in a common plane, supportingelements for each tube arranged intermediately of the ends thereof, saidsupporting elements engaging one another in stacked relation, andfoundation means carrying said supporting elements.

2. In a heat exchanger, the combination of the tubes, and means forconveyin a cooling fluid to and away from the bee ers; of means forsupporting the tubes intermediately of the length thereof including, asupporting block carried by each tube, the blocks engaging one anotherin stacked relation, and a bar removably secured to the shell structurefor carrying said supporting blocks.

In testimony whereof, I have hereunto subscribed my name this 18th dayof Dec.

JOHN A. POTTER.

